简述
DB2数据库使用DRDA协议，DRDA是一个跨IBM平台访问、遵循SQL标准的数据库信息标准。它是IBM的信息仓库框架中的重要组成部分，该框架定义了庞大的后台服务器，客户机可通过较小的基于工作组的中介服务器来访问它，DRDA具有下列功能：
提供了IBM的DB2、DBM、SQL/DS和SQL/400数据库系统的互连框架；
支持多供应商提供的数据库系统；
DRDA是IBM环境中建立客户机/服务器计算的基础之一。其它基础是高级的对等联网(APPN)和分布式数据管理(DDM)。通过信息仓库和DRDA，IBM计算机将它的企业中心组成部分的大型计算机，用作各种类型信息(包括多媒体信息)的存储平台。
报文结构
DRDA报文
DRDA利用TCP传输数据：
通常一个DRDA报文中可以包含一个或者多个DRDA数据结构。
DRDA结构
一个DRDA结构包含一个DDM头：
Length：单个DRDA的长度
Magic: 0xD0
Format： 0x02 Reply Message
0x03 Object Response
0x42 Chained Reply Message, same RC
0x52 Chained Reply Message, different RC
0x53 Chained Object Message, same RC
CorrelID：连接的ID
Length2：Length减去Magic、Format、CorrelID后的长度
Code point: DDM Term Code
数据区可以是Parameters结构，也可以直接用字节流.
Parameters格式如下图：
报文结构格式如下图：
字节码结构如下图:
Length: Parameter的长度
Code point:描述这个数据的用途
Data :数据
字节流如下图：
常用DDM列表
|
DDM Term |
Term Title |
|
Connection establishment to a remote database manager |
|
|
EXCSAT |
Exchange server attributes |
|
ACCRDB |
Access RDB |
|
Package creation/rebind/remove |
|
|
BGNBND |
Begin binding of a package to an RDB |
|
BNDSQLSTT |
Bind SQL Statement to an RDB package |
|
ENDBND |
End binding of a package to an RDB |
|
REBIND |
Rebind an existing RDB package |
|
DRPPKG |
DROP a package at an RDB |
|
Query Processing |
|
|
OPNQRY |
Open query |
|
CNTQRY |
Continue query |
|
CLSQRY |
Close query |
|
Prepare/describe/execute SQL statements |
|
|
PRPSQLSTT |
Prepare SQL statement |
|
DSCSQLSTT |
Describe SQL statement |
|
DSCRDBTBL |
Describe RDB table |
|
EXCSQLSTT |
Execute SQL statement |
|
EXCSQLIMM |
Execute immediate SQL statement |
|
Commit/rollback unit of work |
|
|
RDBCMM |
RDB commit unit of work used by RUOW connections |
|
RDBRLLBCK |
RDB rollback unit of work used by RUOW connections |
|
SYNCCTL |
Sync point control request used for DUOW connections |
|
SYNCRSY |
Sync point resynchronization request used by DUOW connections |
|
Security processing |
|
|
ACCSEC |
Access security |
|
SECCHK |
Security check |
|
Propagating special register settings |
|
|
EXCSQLSET |
SET SQL environment |
|
Connection establishment to a remote database manager |
|
|
EXCSAT |
Exchange server attributes |
|
ACCRDB |
Access RDB |
DDM Reply Data Objects Used by DRDA
|
DDM Term |
Term Title |
|
ACCRDBRM |
Access to RDB completed |
|
ACCSECRD |
Access security reply data |
|
CMDCMPRM |
Command processing completed |
|
ENDQRYRM |
End of query condition |
|
ENDUOWRM |
End unit of work condition |
|
EXCSATRD |
Server attributes reply data |
|
OPNQRYRM |
Open query complete |
|
QRYDSC |
Query answer set description |
|
QRYDTAQ |
Query answer set data |
|
RDBUPDRM |
Update at an RDB condition (Introduced in DRDA Level 2) |
|
RSLSETRM |
RDB result set reply message |
|
SECCHKRM |
Security check complete reply message |
|
SECTKN |
Security token reply data |
|
SQLCARD |
SQL communications area reply data |
|
SQLCINRD |
SQL result set column info reply data |
|
SQLDARD |
SQLDA reply data |
|
SQLDTARD |
SQL data reply data |
|
SQLRSLRD |
SQL result set reply data |
|
SYNCCRD |
Sync point control reply data in support of distributed unit of work |
|
SYNCRRD |
Sync point resynchronization reply data in support of distributed unit of work |
|
SYNCLOG |
Identifies the sync point log used for a unit of work |
|
TYPDEFNAM |
Data type definition name |
|
TYPDEFOVR |
Data type definition override |
常用Parameter
|
Parameter Term |
Term Title |
Term Value of Test |
|
EXTNAM |
External Name |
db2bp |
|
SRVCLSNM |
Server Class Name |
DB2/LINUXX8664 |
|
SRVNAM |
Server Name |
localhost.localdomain |
|
SRVRLSLV |
Server Product Release Level |
SQL09077 |
|
SEMMEC |
Security Mechnism |
0x0009 |
|
RDBNAM |
Relational Database Name |
SNDBADB1 |
|
SECTKN |
Security Token |
Hex String |
|
MGRLVLLS |
Manage Level List |
Hex String |
|
SECCHKCD |
Security Check Code |
0x01 |
|
USRID |
User ID at The Target System |
sndbains |
|
CRRTKN |
Correlation Token |
192.168.85.30.39881.19055161113048 |
|
PRDID |
Product-Specific Identifier |
SQL09077 |
|
TYPDEFNAM |
Data Type Definition Name |
QTDSQLX86 |
|
PKGNAMCSN |
RDB Package Name, Consistency Token and Section Number |
|